04.03.2005 08:50

Getting Smart Battery System (SBS) on an Acer Travelmate 4000 Series Laptop to work with Linux

Yesterday I found an interesting sourceforge-project (sbs-linux [EN]) that deals with supporting the Smart Battery System (SBS) found in some laptops.
As I have some Acer Travelmate 4001LCi laptops at work as platform for my thinclient installation, I always wanted to know the state of my battery. All other laptops work fine with my xbattbar modification, but this model doesn't.

To keep it short: It works now.
Here are the steps one needs to go to get this working:

As you can see, there are several warnings which means, that the patch
provided by sbs-cm is not fully applicable to the DSDT of this laptop. So I
corrected some of these warnings by hand for my DSDT. If your warnings
are similar to mine, you may use my acer-tm4001LCi-sbs-cm.diff instead of the acer-tm4xxx-sbs-cm.diff provided by the sbs-cm package.
With this patch, all warnings (except for the 2033 warnings) are cleaned. If you have any idea of how to get rid of the last four messages, please send me an e-mail.

After completion you should have a "DSDT.aml" file in your CWD. Now you have to add this DSDT to your kernel by either compiling it into your kernel or by using an initrd. I decided the initrd-method, because I already have an initrd for bootsplash and so I only had to append the modified DSDT to my initrd.